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OK.
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So at this point we have a plain Hello World app.
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So say we want to run this app.
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All we need to do is click on play here.
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Here you will see all the emulators that are available, if you click on run you will see the app running
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on the emulator let's give it some time to run.
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OK so here you can see the hello world app that was created out of the box so next we're going to look
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at UI elements. UI is not always important for reverse engineering.
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However there is the aspect of event handlers that might be of interest to us.
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So for example when you click on a button what is actually happening in the code
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Within the code,
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is there any reference to say in edit text within the user interface so for this we're going to create
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a simple button and an edit.
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Text and attach some code to them.
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OK.
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So in the resources, layout, main activity we can see the layout that is associated with the main activity.
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Actually if we go to our main activity we can see the layout we are referring to now in the layout.
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We have two views the design view, which is drag and drop.
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Then we have the text view which is the version of that UI. In the XML,
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you can for example add a text to view by copying and pasting the existing one.
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For example if we add more characters to the copied one we see that there are two text abuse behind
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each other.
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We do not need to go too deep into this but let's just add a button and an edit text for now.
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So first of all in the view you can set it to only see the blueprint.
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Then you can zoom in and out by scrolling in and out with control pressed or just by clicking on the
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zoom buttons OK.
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Let's drop in edit text and a button, if we would have to run this as it is you will see a few inconsistencies.
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So let's run.
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Here you can see they are on top of each other.
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This is because we need to configure the constraints.
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Again this is not too important but let's just make a simple constraint.
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So first thing we're going to add a top inside constraint for the edit text.
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Right now there is a zero default margin.
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Let's change this to 16.
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Next we're going to tell the button to relate it's position based on the edit text physician to do this.
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We're going to right click on the button and do show baseline click on the button and link the baselines
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also from the left side.
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We're going to create a left constraint linking the button to the edit text.
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Now if we run the app again you'll see the edit text on the left with the button on its side.